Category Archives: General/Abdominal

Recommendations for Improved Safety of Lung Ultrasound

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Lung ultrasound (LUS) has been emerging as a vital clinical tool. LUS aids in diagnosing a range of conditions, from pneumonia to respiratory distress syndrome or pulmonary edema. LUS was also very significant at the height of the COVID-19 pandemic, when point-of-care lung monitoring modalities were crucial.  

Diagnostic ultrasound standards and safety guidelines were established in the late 20th century to ensure the safety of ultrasound imaging and avoid ultrasound bioeffects in tissues. The Thermal Index (TI) and Mechanical index (MI) are two ultrasound exposure indices that respectively indicate the risks of tissue heating and cavitation and which must be displayed in real time during scanning. However, the lung is a tissue like no other, and the bioeffects observed in animal studies (in mice, rabbits, pigs, and monkeys) are very different from the bioeffects observed in other tissues. Capillary pulmonary hemorrhage is a unique bioeffect that is correlated to the MI. In order to avoid such specific ultrasound bioeffects, a new safety paradigm must be created for LUS.

Despite guidelines recommending MI ≤ 0.4, recent research suggests that a further reduction to MI ≤ 0.3 for enhanced safety might be needed. In addition, it is critical to account for the actual MI in situ, which is influenced by the thickness of the chest wall. This is particularly concerning in neonatal LUS safety, due to thin chest walls and intensive use.

Existing safety education varies among practitioners, and surveys indicate a lack of knowledge regarding lung ultrasound safety. In the absence of an appropriate preset, pre-installed on all machines, for neonatal LUS guaranteeing an MI ≤ 0.3, the risk of error and exposure to higher MI is significant. In pediatric and adult patients with a thicker chest wall, a higher MI would be acceptable, as long as adherence to the “as low as reasonably achievable” (ALARA) safety principle is maintained.

Overall, the recommendations for Improved Safety  of Lung Ultrasound are:

  1. To install a preset on all ultrasound machines limiting MI to ≤ 0.3 for neonatal cases.
  2. To provide a user-friendly means for practitioners to select the safety preset without manual adjustments.
  3. To allow higher MI values for pediatric and adult patients when needed for optimal imaging, considering higher ultrasound attenuation in thicker chest walls.
  4. To guide practitioners in adhering to the As Low As Reasonably Achievable (ALARA) principle and by considering the chest wall attenuation for MI > 0.3.
  5. To develop a specific Mechanical Index for Lung (MIL). The creation of a unique MIL for LUS, displayed on-screen to estimate pleural exposure accurately would increase safety and safety awareness among practitioners.

Enhancing safety in LUS requires a multifaceted approach, encompassing preset implementation, practitioner education, and technological advancements. The proposed recommendations aim to address current safety challenges, ensuring the continued effectiveness and safety of lung ultrasound in diverse clinical settings and for diverse populations (from neonates to high BMI patients). By combining technological innovations with user-friendly controls, the proposed safety paradigm seeks to strike a balance between optimal imaging outcomes and patient safety in the evolving landscape of LUS.

For more information, see the “Statement and Recommendations for Safety Assurance in Lung Ultrasound” from the American Institute of Ultrasound in Medicine (AIUM)

Marie Muller, PhD, is an Associate Professor of Mechanical and Aerospace Engineering at NC State University.

You Won’t Be Left in the Dark at UltraCon (except during the total eclipse!)

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Have you considered how you will spend April 8 (well, April 6–10, 2024, actually)? The place to be on the 8th is somewhere you can be in the path of totality during the total solar eclipse, and what better place to be than Austin, TX, where you can see the eclipse and get your fill of everything ultrasound?

(and probably the cheapest way to get a hotel room is to register for UltraCon 2024 and grab a room while we still have affordable rooms in our block).

The AIUM brings our annual meeting to Austin, TX, for the first time, and there will be lots to take in. We are bringing back Educational Tracks. No matter where your interests lie, MSK or Fetal Echo or General US or OB or GYN, there is a track for you! There is something for you, whether you are early in your career or an experienced sonographer/sonologist. You will hear presentations from experts that will keep you up to date on changes in the field and tell you what is coming down the pike. For our members who are deep into the basic sciences, some presentations will stimulate new thinking and show you what other colleagues are up to. One of the best parts of the program is that you aren’t stuck in one track—you can mix and match to customize your experience. Check out the tracks here.

UltraCon brings you more than just the educational tracks. Is there a product that you have always wanted to develop and commercialize? Perhaps an invention, a training program, or another idea you are sure could be monetized? If so, the AIUM’s Shark Tank is for you! Put together your best proposal and present it to our panel of experts from industry, venture capital, and academia. $1,000 is up for grabs, but win or lose, you will gain valuable insights and critical appraisal of your concept, along with suggestions for what you need to do to take your proposal to the next step.

Scientific sessions run throughout the meeting, allowing you to hear cutting-edge research that will help answer some of the questions you might be having or possibly give you ideas to pursue on your own. You will hear from young researchers just starting out their careers as well as experienced scientists who have gotten us where we are today but aren’t done leading us yet.

One of the best aspects of the annual meeting is the chance to hear from luminaries and others with cutting-edge ideas, whether in ultrasound directly or in fields that will impact ultrasound, such as artificial intelligence and other new technologies. This year’s plenary sessions will be captivating as we hear from Dr Omar Ishrak on the future of ultrasound technology and from Dr Gil Weinberg on an amazing application of ultrasound to offer amputees the opportunity to play musical instruments.

Other talks will cover how CPT codes are developed, how to efficiently complete your application for accreditation, and so much more that will round out your experience in Austin.

UltraCon 2024 promises to be a Top Shelf event that you really don’t want to miss—and yes, we have scheduled a break to go outside to see the eclipse, so you won’t be asked to decide between these 2 once-in-a-lifetime events! Note that our hotel block is probably the least expensive deal in town, as our rates were negotiated years ago before many were paying attention to this eclipse. It is entirely possible we will sell out our block of rooms, so make your plans and register as soon as possible!

David C. Jones, MD, FACOG, FAIUM, the AIUM’s President Elect, is a Professor at the University of Vermont and the Director of the Fetal Diagnostic Center at the University of Vermont Medical Center.

Ultrasound in the Diagnosis and Management of Chronic Obstructive Pulmonary Disease

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Chronic Obstructive Pulmonary Disease (COPD) is a prevalent and debilitating respiratory condition that affects millions of people worldwide. While traditional diagnostic methods like spirometry and imaging techniques such as CT scans have played a vital role in managing this disease, ultrasound is emerging as a powerful tool in both diagnosis and treatment.

The Basics of COPD

COPD is a progressive lung disease characterized by the restriction of airflow due to chronic bronchitis and emphysema. The primary symptoms include breathlessness, coughing, and excessive mucus production. It is typically associated with a history of smoking, but environmental factors also play a role. Diagnosing and monitoring the progression of COPD is crucial for effective management.

The Role of Ultrasound in Diagnosis

Sonographic Assessment of Lung Morphology: Ultrasound imaging offers a noninvasive and radiation-free approach to assess lung morphology. Studies published in the Journal of Ultrasound in Medicine have demonstrated the effectiveness of ultrasound in evaluating lung parenchyma,1 pleura,1 and diaphragm.2 By examining these elements, clinicians can identify changes in the lung structure and rule out other conditions that might mimic COPD symptoms.

Evaluation of Diaphragm Function: COPD often affects diaphragm function, resulting in respiratory muscle weakness. Ultrasound allows for real-time assessment of diaphragm movement, enabling clinicians to detect early signs of diaphragmatic dysfunction.2 This information is valuable in selecting the appropriate treatment strategy for each patient.

Ultrasound-Guided Thoracentesis

In some cases, COPD patients develop pleural effusion, a condition characterized by an abnormal buildup of fluid in the pleural cavity. Ultrasound can be used to guide thoracentesis, a procedure in which this excess fluid is drained. A Journal of Ultrasound in Medicine report has highlighted the accuracy and safety of ultrasound guidance during this procedure, minimizing complications and improving patient outcomes.3

Monitoring Disease Progression

Ultrasound is not limited to the initial diagnosis but also plays a crucial role in monitoring COPD progression. Repeat ultrasound examinations can help evaluate changes in lung structure, assess diaphragm function, and track the effectiveness of ongoing treatments. Regular ultrasound monitoring can lead to more tailored and effective care plans for COPD patients.

Point-of-Care Ultrasound in COPD

Point-of-care ultrasound (POCUS) is a valuable tool for quickly assessing COPD exacerbations in emergency situations. It allows healthcare providers to rapidly evaluate lung abnormalities, pneumothorax, and pleural effusion, guiding immediate treatment decisions.4

Future Implications

As technology continues to advance, ultrasound is likely to play an even more prominent role in the diagnosis and management of COPD. Developments in portable and handheld ultrasound devices are making it easier for clinicians to perform ultrasound examinations at the bedside, providing real-time information to aid in decision-making.

Conclusion

The use of ultrasound in the diagnosis and management of COPD is a promising and evolving field. It offers a noninvasive, safe, and cost-effective means of assessing lung morphology, diaphragm function, and pleural effusion. With continued research and technological advancements, ultrasound is likely to become an indispensable tool in the fight against this chronic respiratory disease, helping patients receive more accurate diagnoses and tailored treatment plans.

References:

1. Martelius L, Heldt H, Lauerma K. B-lines on pediatric lung sonography: comparison with computed tomography. J Ultrasound Med 2016; 35:153–157. doi: 10.7863/ultra.15.01092.

2. Xu JH, Wu ZZ, Tao FY, et al. Ultrasound shear wave elastography for evaluation of diaphragm stiffness in patients with stable COPD: A pilot trial. J Ultrasound Med 2021; 40:2655–2663. doi: 10.1002/jum.15655.

3. Lane AB, Petteys S, Ginn M, Nations JA. Clinical importance of echogenic swirling pleural effusions. J Ultrasound Med 2016; 35:843–847. doi: 10.7863/ultra.15.05009.

4. Copcuoglu Z, Oruc OA. Diagnostic accuracy of optic nerve sheath diameter measured with ocular ultrasonography in acute attack of chronic obstructive pulmonary disease. J Ultrasound Med 2023; 42:989–995. doi: 10.1002/jum.16106.

Cynthia Owens, BA, is the Publications Coordinator for the American Institute of Ultrasound in Medicine (AIUM).

Interested in learning more about lung ultrasound? Check out the following articles from the American Institute of Ultrasound in Medicine’s (AIUM’s) Journal of Ultrasound in Medicine (JUM). After logging into the AIUM, members of AIUM can access them for free. Join the AIUM today!

How Can Ultrasound Contrast Agents Be Used to Sensitize Tumors to Radiation?

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Ultrasound contrast agents (UCAs) have the ability to go throughout the body and reach anywhere there is active vascularity. As clinicians and scientists, we use this to our advantage for diagnostic and therapeutic purposes. A unique characteristic of a UCA is its ability to generate nonlinear responses at sufficient pressure. These nonlinear responses produce harmonics in an acoustic field. UCAs undergo natural oscillations, and, at higher pressures, these UCAs can produce bioeffects. Inertial cavitation is the transient destruction of UCAs from increased pressure, while stable cavitation is a constant oscillation. Both of these cavitation states can produce shear stress on vessel walls, particularly endothelial cells.

Endothelial cells are the cell layer that lines all blood vessels in the body and are responsible for many functions but primarily control the passage of nutrients into tissues.1 In normal tissue, endothelial cells are uniform and form an organized monolayer network with tight junction connections.1 However, in tumor endothelial cells (TECs), it is much more of a chaotic process. In TECs, long, fragile cytoplasmic projections extend into the vessel lumen, creating small openings and gaps in the vessel wall.1 In addition to smaller gaps, larger openings (up to 1.5 µm) have also been identified, which make cell closures more difficult. These small and large gaps in TECs can be harnessed to produce endothelial cell apoptosis by destroying UCAs via inertial cavitation. Utilizing inertial cavitation has been shown to produce endothelial cell apoptosis (cell death) by generating bioeffects (ie, shock waves, microjets, micro streams, and thermal effects) that mechanically perturb TEC membranes.

Moreover, there are many components to a cell membrane, which goes beyond the scope of this blog post; however, sphingolipids are an essential enzyme to a cell membrane.2 Sphingolipids help maintain cellular homeostasis and are closely associated with cellular biologic functions, such as proliferation, apoptosis, or oxidative stress on endothelial cells.2 Some sphingolipids, such as ceramide, are important second signaling molecules that determine cell proliferation or death.

Traditionally, radiation therapy has been thought to act by damaging the DNA of cells via double and single DNA strand breaks, resulting in apoptosis. However, more recent studies have suggested that blood vessels are the determining factor of tumor response to radiation therapy at high doses (>8–19 Gy).3 Endothelial cells exposed to high doses of radiation upregulate the acid-sphingomyelinase pathway (ASMASE), which hydrolyzes sphingomyelin (dominant sphingolipid) into apoptosis, with ceramide acting as the second messenger. El Kaffas et al suggest that a primary factor why endothelial cells respond differently than other cell types is because endothelial cells have a 20x enrichment of a nonlyosomal secretory form of the ASMASE enzyme.4,5 This enzyme is associated with membrane remodeling, restructuring, responses to shear stress, and activation of ceramide from cell stressors.6,7 Additionally, endothelial cells are more sensitive to shear stress and mechanical forces.4 Radiation therapy and inertial cavitation treatments separately have been shown to produce tumor cell death. Combining these two treatments results in an increased accumulation of ceramide production and apoptosis, leading to improved tumor radiosensitivity.

Over the past decade, primarily in pre-clinical research, the benefits of combining microbubbles and radiation have been shown. From one of the original pre-clinical studies validating this concept, Czarnota et al showed that inertial cavitation and radiation therapy in a human prostate xenograft model in mice led to a 10-fold increase in ceramide-related endothelial cell death, confirming the benefits of the combined relationship.7 In addition, the study demonstrated a significant effect with a decreased radiotherapy dose (2 Gy versus 8 Gy) when combined with inertial cavitation compared to stand-alone treatment regimens. This mechanism has mainly been validated with in vivo studies. However, my group at Thomas Jefferson University has a first-ever pilot clinical trial incorporating ultrasound-triggered microbubble destruction (UTMD) to sensitize hepatocellular carcinoma in patients that receive the locoregional therapy, trans-arterial radioembolization (TARE).8 In an interim analysis, there was a greater prevalence of tumor response in the patients receiving TARE plus UTMD as opposed to in those who received TARE alone. Additionally, lab values and liver function tests demonstrated no significant differences between study groups, indicating that adding microbubble cavitation does not affect patient safety or liver functions.

This study is an ongoing clinical trial and will complete enrollment within the next 6 months, and this concept has been incorporated in non-HCC tumors in an ongoing pilot clinical trial at Thomas Jefferson University (NCT# 03199274). As a result of our research to date, we have learned that incorporating UTMD with radiation therapy may help sensitize tumors for improved survival and treatment outcomes. Additional clinical research is needed in this field because the combination treatment regimen may be easily incorporated into non-liver tumors.

References

  1. Dudley AC. Tumor endothelial cells. Cold Spring Harb Perspect Med 2012; 2:a006536. doi: 10.1101/cshperspect.a006536.
  2. Lai Y, Tian Y, You X, Du J, Huang J. Effects of sphingolipid metabolism disorders on endothelial cells. Lipids Health Dis 2022: 21(1):101. doi: 10.1186/s12944-022-01701-2.
  3. Paris F et al. Endothelial apoptosis as the primary lesion initiating intestinal radiation damage in mice. Science 2001; 293(5528):293–297. doi: 10.1126/science.1060191.
  4. El Kaffas A and Czarnota GJ. Biomechanical effects of microbubbles: from radiosensitization to cell death. Future Oncol 2015; 11(7):1093–1108. doi: 10.2217/fon.15.19.
  5. Tabas I. Secretory sphingomyelinase. Chem Phys Lipids 1999; 102(1):123–130. doi: 10.1016/S0009-3084(99)00080-8.
  6. El Kaffas A, Al-Mahrouki A, Hashim A, Law N, Giles A, Czarnota GJ. Role of acid sphingomyelinase and ceramide in mechano-acoustic enhancement of tumor radiation responses. J Natl Cancer Inst 2018; 110(9):1009–1018. doi: 10.1093/jnci/djy011.
  7. Czarnota GJ et al. Tumor radiation response enhancement by acoustical stimulation of the vasculature. Proc Natl Acad Sci U S A  2012; 109(30): E2033-E2041. doi: 10.1073/pnas.1200053109.
  8. Eisenbrey JR et al. US-triggered microbubble destruction for augmenting hepatocellular carcinoma response to transarterial radioembolization: a randomized pilot clinical trial. Radiology 2021; 298:450–457. doi: 10.1148/radiol.2020202321.

Corinne Wessner, MS, MBA, RDMS, RVT, is a research sonographer at Thomas Jefferson University and a PhD candidate at Drexel University in the School of Biomedical Engineering, Science and Health Systems in Philadelphia, PA. She is also Vice Chair of the American Institute of Ultrasound in Medicine’s (AIUM’s) High-Frequency Clinical and Preclinical Imaging Community (2023–2025).

Interested in reading more from Corinne Wessner? Check out these articles from the Journal of Ultrasound in Medicine (JUM). Members of AIUM can access them for free after logging in to the AIUM. Join the AIUM today!):

Lymphosonography: The use of contrast-enhanced ultrasound as a lymphatic mapping technique

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Ipsilateral axillary diagnostic ultrasound is part of the initial staging for breast cancer to evaluate lymph nodes using a b-mode classification where certain aspects, when present, increase the level of suspicion for metastatic disease, such as cortical thickening and poor hilar visibility.1–3 Diagnostic ultrasound is also used as a method to guide biopsies of the suspicious lymph nodes.1

The majority of patients will have no suspicious lymph nodes findings at the time of diagnosis, the lymphatic system mapping after the injection of blue dye and/or a radioactive tracer followed by a surgical excision becomes the only way to determine the final stage of disease. However, these methods have limitations such as the use of radiation and lack of an imaging component.

In the past, ultrasound could not be used for lymphatic mapping, since mapping requires administration of a tracer. This changed with the use of contrast-enhanced ultrasound (CEUS) to detect lymph nodes after subcutaneous injections of microbubble-based ultrasound contrast agents (UCA), termed “lymphosonography”.4–6 The development of the lymphosonography technique addressed the limitations of the currently used lymphatic mapping techniques.

Our group conducted a clinical trial to evaluate the efficacy of CEUS lymphosonography in the identification of sentinel lymph nodes (SLN) in patients with breast cancer undergoing surgical excision following the injection of blue dye and radioactive tracer as part of their standard of care using pathology results for malignancy as a reference standard.6,7

In the clinical trial, 86 subjects were enrolled and 79 completed the study. The subjects received 4 subcutaneous injections of ultrasound contrast agent around the tumor, for a total of 1.0 ml. A clinical ultrasound scanner with CEUS capabilities was used to identify SLNs. After the ultrasound study examination, the subjects received blue dye and radioactive tracer for guiding SLN excision as part of their standard of care. The SLNs excised during the standard-of-care surgical excision were classified as positive or negative for presence of blue dye, radioactive tracer and UCA, and sent for pathology to determine presence or absence of metastatic involvement.

Example of a sentinel lymph node (SLN) seen with lymphosonography. The arrow indicates the SLN. The arrowhead indicates the lymphatic channel.

A total of 252 SLNs were excised from the 79 subjects. Of the 252 SLNs excised, 158 were positive for blue dye, 222 were positive for radioactive tracer and 223 were positive for UCA. Statistical comparison showed that compared with the reference standards, lymphosonography showed similar accuracy with radioactive tracer (p > 0.15) and higher accuracy (p < 0.0001). The pathology results showed that, of the 252 SLNs excised, 34 had metastatic involvement and were determined malignant by pathology. Of these 34 SLNs, 18 were positive for blue dye (detection rate of 53%), 23 were positive for radioactive tracer (detection rate of 68%) and 34 were positive for UCA (detection rate of 100%; p < 0.0001).

The conclusion of this study indicates that lymphosonography had similar accuracy as the standard-of-care methods for identifying SLNs in breast cancer patients, with the added advantage of an imaging component that allows for a preoperative evaluation of SLNs and that lymphosonography may be a more specific and precise approach to SLN identification in patients with breast cancer.6

Larger multicenter clinical trials are necessary to be able to translate this technique to the clinical setting and to be able to incorporate it as part of the breast cancer patients’ standard of care.

  1. Voit CA, van Akkooi ACJ, Schäfer-Hesterberg G, et al. Rotterdam Criteria for sentinel node (SN) tumor burden and the accuracy of ultrasound (US)-guided fine-needle aspiration cytology (FNAC): can US-guided FNAC replace SN staging in patients with melanoma? J Clinical Oncol 2009; 27(30):4994–5000.
  2. Dialani V, Dogan B, Dodelzon K, Dontchos BN, Modi N, Grimm L. Axillary imaging following a new invasive breast cancer diagnosis—A radiologist’s dilemma. J Breast Imaging 2021; 3:645–658.
  3. Chang JM, Leung JWT, Moy L, Ha SM, Moon WK. Axillary nodal evaluation in breast cancer: state of the art. Radiology 2020; 295:500–515.
  4. Goldberg BB, Merton DA, Liu J-B, Thakur M, et al. Sentinel lymph nodes in a swine model with melanoma: contrast-enhanced lymphatic US. Radiology 2004; 230:727–734.
  5. Goldberg BB, Merton DA, Liu J-B, Murphy G, Forsberg F. Contrast‐enhanced sonographic imaging of lymphatic channels and sentinel lymph nodes. J Ultrasound Med 2005; 24:953–965. doi: 10.7863/jum.2005.24.7.953.
  6. Machado P, Liu J-B, Needleman L, et al. Sentinel lymph node identification in patients with breast cancer using lymphosonography. Ultrasound Med Biol 2023; 49:616–625. Epub 2022 Nov 26.
  7. Machado P, Liu JB, Needleman L, et al. Sentinel lymph node identification in post neoadjuvant chemotherapy breast cancer patients undergoing surgical excision using lymphosonography. J Ultrasound Med 2023; 42:1509–1517. doi: 10.1002/jum.16164. Epub 2023 Jan 2.

Priscilla Machado, MD, FAIUM, is a Research Assistant Professor in the Department of Radiology at Thomas Jefferson University in Philadelphia, PA.

Interested in learning more about ultrasound? Check out these posts from the Scan:

Predicting Risk of 30-Day Readmission in Heart Failure Patients

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Pulmonary congestion is the most frequent cause of heart failure hospitalizations and readmissions. In addition, approximately 20%–25% of heart failure patients aged 65 years and older in the United States are readmitted within 30-days after hospital discharge,1–5 despite efforts to identify predictors of readmission for acute decompensated heart failure (ADHF), such as laboratory markers, the readmission rates remain high. Lung ultrasound (LUS), however, has been shown to be a valuable tool for assessing pulmonary congestion, providing a reliable assessment based on the presence of B-lines.

A recent study by Cohen et al7 evaluated the association between lung ultrasound findings and the risk of 30-day readmission among HF patients, hypothesizing that a higher number of positive B-line lung fields on LUS will indicate an increased risk of readmission. Using a log-binomial regression model in an 8-zone LUS exam from the day of discharge, the researchers assessed the risk of 30-day readmission associated with the number of lung zones positive for B-lines, considering a zone positive when ≥3 B-lines were present. According to the results from 200 patients, the risk of 30-day readmission in patients with 2–3 positive lung zones was 1.25 times higher (95% CI: 1.08–1.45), and in patients with 4–8 positive lung zones was 1.50 times higher (95% CI: 1.23–1.82), compared with patients with 0–1 positive zones, after adjusting for discharge blood urea nitrogen, creatinine, and hemoglobin.

Ultrasound image of a lung
Ultrasound image of a lung with B-lines. The pleural line is indicated by the arrow. Emanating from the pleural line are hyperechoic reverberation artifacts, which are B-lines (indicated by the star), indicating the presence of fluid within the interstitium of the lung.

A recent study by Cohen et al7 evaluated the association between lung ultrasound findings and the risk of 30-day readmission among HF patients, hypothesizing that a higher number of positive B-line lung fields on LUS will indicate an increased risk of readmission. Using a log-binomial regression model in an 8-zone LUS exam from the day of discharge, the researchers assessed the risk of 30-day readmission associated with the number of lung zones positive for B-lines, considering a zone positive when ≥3 B-lines were present. According to the results from 200 patients, the risk of 30-day readmission in patients with 2–3 positive lung zones was 1.25 times higher (95% CI: 1.08–1.45), and in patients with 4–8 positive lung zones was 1.50 times higher (95% CI: 1.23–1.82), compared with patients with 0–1 positive zones, after adjusting for discharge blood urea nitrogen, creatinine, and hemoglobin.

This study adds to the research on LUS in patients with HF in inpatient or intensive care units and emergency departments, including studies on identifying pulmonary congestion to reduce decompensation in heart failure patients,7 the risk of hospitalization or all-cause death was greater in patients with more B-lines at discharge,8 and the prognostic value of LUS as an independent predictor of 90-day readmission.9,10

The study by Cohen et al7 expands on the prior research and demonstrates the prognostic importance of more B-lines at discharge for HF patients. Failure to relieve congestion before discharge is associated with increased morbidity and mortality and is a strong predictor of poor outcomes in patients with acute decompensated HF.

By evaluating HF patients with LUS, we may be better able to risk-stratify the severity of asymptomatic pulmonary congestion on discharge and identify patients at higher risk of readmission.

References

  1. Desai AS, Stevenson LW. Rehospitalization for heart failure: predict or prevent? Circulation 2012; 126:501–506.
  2. Suter LG, Li SX, Grady JN, et al. National patterns of risk-standardized mortality and readmission after hospitalization for acute myocardial infarction, heart failure, and pneumonia: update on publicly reported outcomes measures based on the 2013 release. J Gen Intern Med 2014; 29:1333–1340.
  3. Yancy CW, Jessup M, Bozkurt B, et al. 2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. Circulation 2013; 128:e240–e327.
  4. Tavares LR, Victer H, Linhares JM, et al. Epidemiology of decompensated heart failure in the city of Niter_oi: EPICA -Niter_oi Project. Arq Bras Cardiol 2004; 82:125–128.
  5. Cleland JG, Swedberg K, Cohen-Solal A, et al. The Euro Heart Failure Survey of the EUROHEART survey programme. A survey on the quality of care among patients with heart failure in Europe. The study group on diagnosis of the working group on heart failure of the European Society of Cardiology. The medicines evaluation Group Centre for Health Economics University of York. Eur J Heart Fail 2000; 2:123–132.
  6. Cohen A, Li T, Maybaum S, et al. Pulmonary congestion on lung ultrasound predicts increased risk of 30-day readmission in heart failure patients [published online ahead of print February 25, 2023]. J Ultrasound Med. doi: 10.1002/jum.16202.
  7. Araiza-Garaygordobil D, Gopar-Nieto R, Martinez-Amezcua P, et al. A randomized controlled trial of lung ultrasound-guided therapy in heart failure (CLUSTER-HF study). Am Heart J 2020; 227:31–39.
  8. Platz E, Lewis EF, Uno H, et al. Detection and prognostic value of pulmonary congestion by lung ultrasound in ambulatory heart failure patients. Eur Heart J 2016; 37:1244–1251.
  9. Gargani L, Pang PS, Frassi F, et al. Persistent pulmonary congestion before discharge predicts rehospitalization in heart failure: a lung ultrasound study. Cardiovasc Ultrasound 2015; 13:40.
  10. Coiro S, Rossignol P, Ambrosio G, et al. Prognostic value of residual pulmonary congestion at discharge assessed by lung ultrasound imaging in heart failure. Eur J Heart Fail 2015; 17:1172–1181.

To read more about this study, download the Journal of Ultrasound in Medicine article, “Pulmonary Congestion on Lung Ultrasound Predicts Increased Risk of 30-Day Readmission in Heart Failure Patients” by Allison Cohen, MD, et al. Members of the American Institute of Ultrasound in Medicine (AIUM) can access it for free after logging in to the AIUM. Join the AIUM today!

Interested in reading more about ultrasound? Check out these posts from the Scan:

SLOW DOWN: Take Your Time in Diagnosing PCOS in Adolescents

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Polycystic ovarian syndrome (PCOS) is the most common ovulation disorder among adult reproductive-age women. This blog post will discuss the latest recommendations, which state that we should wait about 8 years after menarche to make this diagnosis in adolescents!

PCOS is defined by the Rotterdam Criteria as 2 of the following: irregular menstrual cycles (or absent cycles), hirsutism (clinically as acne or male-patterned hair growth or elevated androgens), and polycystic-appearing ovaries on ultrasound, also known as PCO morphology. In addition, other disorders that may look like PCOS need to be ruled out (thyroid disease, hyperprolactinemia, adrenal disorders). The two main areas where patients or providers have difficulty are how cycle lengths are determined and PCO morphology.

In gynecology and infertility, we see a number of women with irregular menstrual cycles. Irregular menstrual cycles are defined as cycles occurring more frequently than every 21 days or less frequently than every 35 days from the beginning of one cycle to the beginning of the next cycle (cycle day 1 to cycle day 1). Some patients get confused and count from the last day of bleeding to the first day of the next period, which artificially makes the cycle seem short. It is good to keep a menstrual calendar (a regular calendar where each day of bleeding is marked with an “X” and review it over a couple of months). It is easy to count the number of days from the beginning of one menstrual cycle to the beginning of the next when counting from the first “X” of one cycle to the first “X” of the next.

One manner of identifying polycystic ovaries is by the volume: If one or both ovaries has a volume of more than 10 cm3 then that meets the criteria for a polycystic ovary on ultrasound.

The other method of identification is counting and measuring follicles. Counting antral follicles, which are follicles that measure as less than 10 mm in diameter, in a polycystic-appearing ovary can be difficult. First, check to see if there are any cysts in the ovary (any large, space-occupying mass greater than 10 mm). If cysts larger than 10 mm are present, then the antral follicle counts and the ovarian volumes will be distorted. Typically, it is easiest to measure the antral follicles and ovarian volume in the early follicular phase, or cycle days 1–5 (where cycle day 1 is the first day of the menstrual period). In this early part of the menstrual cycle, there should not be a dominant follicle growing yet so the ovary commonly has only small antral follicles at this time in the cycle.

Originally, polycystic-appearing ovaries were described as having antral follicles lined up in the periphery of the ovary or a “pearl necklace” sign. In PCOS, the stroma of the ovary produces the androgens, and patients with PCOS tend to have a greater stromal area. However, the Rotterdam criteria did not use these descriptions in defining a polycystic-appearing ovary. Instead, the Rotterdam criteria state a volume or an antral follicle count when there are no cysts. The antral follicle count was initially described in the Rotterdam criteria as either ovary with more than 12 follicles (2–9 mm).

Unfortunately, with this number, a number of adolescents were being misdiagnosed with PCOS. Why would that be?

There are two reasons: one, when girls have menarche, the hypothalamic pituitary ovary axis is not mature and they will have irregular cycles—sometimes this irregularity lasts a couple of years. So, many adolescents were noted to have met the “irregular cycles” criterion. Second, adolescents have an excellent ovarian reserve. They should have a lot of antral follicles because they have a lot of eggs in the early part of their reproductive years. These ovaries are sometimes referred to as multi-follicular ovaries. This is a normal finding.  

Consequently, the international guideline, which has been adopted by the ESHRE (European Society of Human Reproduction and Embryology) and the ASRM (American Society of Reproductive Medicine) has concluded that the number of follicles needed to meet the PCO-appearing criteria should be 20 or more antral follicles (2–9 mm) in either ovary and others recommend 25 or more antral follicles.

They all accept that an ovary larger than 10 mL would meet the criterion. In addition, they have stated that we should NOT make the diagnosis of PCOS in adolescents within 8 years of their menarche because the reproductive axis is not mature early after menarche. Others have recommended NOT using the ultrasound criteria as an independent marker in diagnosing adolescents.

In other words, adolescents will need to have evidence of hirsutism and anovulation to meet the criteria of PCOS. The general consensus is that we do not want to inappropriately place a label of PCOS on these young women. PCOS has a lot of medical sequelae such as infertility, increased risk for insulin resistance, metabolic syndrome, diabetes, hypertension, and many others that could unnecessarily worry the young women.

Take home message: Be SLOW to diagnose PCOS in Adolescents! 

References:

Teede HJ, Misso ML, Costello MF, Dokras A, Laven J, Moran L, Piltonen T, Norman RJ and International PCOS Network. Recommendations form the international evidence-based guideline for the assessment and management of polycystic ovary syndrome. Hum Reprod 2018; 1–17. Doi:10.1093/humrep/dey256

Al Wattar BH, Fisher M, Bevington L, Talaulikar V, Davies M, Conway G, Yasmin E. Clinical practice guidelines on the diagnosis and management of polycystic ovary syndrome: a systematic review and quality assessment study. J Clin Endocrinol Metab 2021; 106(8):2436–2446.

Dumesic DA, Oberfield SE, Stener-Victorin E, Marshall JC, Laven JS, Legro RS. Scientific statement on the diagnostic criteria, epidemiology and pathophysiology, and molecular genetic of polycystic ovary syndrome. Endocrine Reviews 2015; 36(5):487–525. https://doi.org/10.1210/er.2015-2018

https://www.endocrine.org/advancing-research/scientific-statements/polycystic-ovary-syndrome

Elizabeth E. Puscheck, MD, MS, MBA, FACOG, FAIUM, is a board-certified Reproductive Endocrinologist practicing with InVia Ferility and a tenured Professor at Wayne State University School of Medicine.

Impact of Ultrasound on Medical Imaging: 1967–2021

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In 1967, a weekly feature for medical school seniors was the ‘bullpen’ in the Charity Hospital amphitheater. Students were assigned a patient and given 30 minutes to do a history and physical exam and then present their differential diagnosis and recommendations to an attending. Diagnosis was almost exclusively based on the history and physical examination. Laboratory studies were generally confined to basic electrolytes, a CBC, urinalysis, sputum stains, and a chest x-ray.

This prepared me well for internship and residency on the Osler Medical Service at Johns Hopkins Hospital. Interns were on call 24 hours a day for 6 days a week and usually spent 16 to 18 hours a day attending patients at the bedside.

On Osler, there were no computers and handwritten or typed paper records hung on a chart rack. The wards were not air-conditioned, and yellow curtains separated each of the 28 beds. There were no patient monitors, IV pumps, or respirators, and interns performed all of the basic lab work on their patients. Nursing care was excellent; the house staff and nurses worked as a team caring for the patients. Lack of technology was compensated for by close and direct interaction with the patients and their families, and the practice of medicine was extremely satisfying and filled with empathy and compassion.

The patient was the object of all of our attention. In the late 1960s, imaging was limited and played a relatively minor role in diagnosis and management. Defensive medicine was not a concern.

Following my internal medicine residency at Hopkins, I spent the next 3 years in the immunology branch of the National Cancer Institute in Bethesda. The research centered on the new field of bone marrow transplantation and treatment of graft vs. host disease.1 Whole-body radiation prepared candidates for transplantation and my experience in dealing with near-lethal doses of radiation led me to pursue a career in radiation oncology.

After completing a residency in general and therapeutic radiology in 1975, I joined the staff of the Ochsner Clinic in New Orleans, practicing a combination of radiation therapy and general radiography and fluoroscopy. Imaging was film-based, with studies hung on multipanel viewboxes for interpretation and a hot light for image processing. Cases were dictated directly to a transcriptionist in a cubicle next to the reading room and were typed and signed in real time. The daily workload included 40 to 50 barium studies along with numerous oral cholecystograms, intravenous urograms, and chest and bone radiographs. Specialized imaging consisted of polytomography, penumoencephalography, lymphangiography, and angiography. Evaluation of the aorta, runoff vessels, and carotid vessels was performed by direct puncture. Women’s imaging consisted of xeromammograms, hysterosalpingography, and pelvimetry. Image-guided intervention was nonexistent.

That year, ultrasound was in its early clinical development and I acquired a machine and placed it in the radiation therapy department and began scanning patients from the nearby emergency department. At that time there were no other sectional imaging modalities (CT was not yet available for clinical use.).

A large part of the challenge of ultrasound was learning anatomy in a completely new way. As a result, my groundwork in understanding sectional anatomy came from ultrasound. Ultrasound, unlike CT and MR, permitted imaging not only in standardized axial planes but allowed scan planes in virtually any orientation, requiring a very detailed knowledge of anatomy.

In 1976, upon the retirement of Dr. Seymour Ochsner, I became Chair of the department at Ochsner. This provided me with an opportunity to re-equip the department at a time that the entire field of imaging was undergoing immense change. With ultrasound, new findings were being reported regularly2, and the overall quality of ultrasound images often exceeded those of early body CT scans.

The development of Doppler ultrasound in the late 1970s further expanded the applications of ultrasound, although prior to the introduction of color Doppler, this was mainly of interest to vascular surgeons, and diagnosis was based on waveform analysis rather than imaging.

An important technological development at the end of the 1970s was real-time ultrasound, leading to the rapid development of new applications in obstetrical, abdominal, pediatric, and intraoperative imaging3,4.

Developments in computers in the early 1980s led me to an opportunity to participate in the development of exciting new technologies, including a breakthrough involving ultrasound and providing a method to image Doppler information. Working with a small company in Seattle and a large prototype device, we generated the first images of blood flow in the abdomen and peripheral vessels using color Doppler5,6. Color Doppler, by allowing Doppler information to be shown in an image rather than as a waveform, was important in getting radiologists interested in Doppler. Today, color Doppler is an integral part of the ultrasound examination.

A less successful application of ultrasound in the 1980s was in the evaluation of the breast. Early breast scanners produced quality images by scanning the breast, as the patient lay prone in a water tank. Unfortunately, breast ultrasound was promoted aggressively by many manufacturers and by the mid-1980s was discredited as a useful addition to mammography. By the mid-1990s, however, advances in breast ultrasound demonstrated an important role in the evaluation of breast masses, making ultrasound an indispensable part of breast imaging and leading to the BI-RADS breast imaging and reporting system for ultrasound7–9.

Ultrasound also has had a major impact in providing guidance for minimally invasive diagnostic procedures. Fine-needle biopsy of lesions of the liver, kidney, retroperitoneum, as well as peripheral lymph nodes and the thyroid, have become a standard part of the diagnostic workup.

A radiologist of 50 years ago would not recognize the field if he or she were to return today. In fewer than 50 years, the computer has changed the practice of medicine. More precise and early diagnosis are clear benefits of the technology of the 21st century, but are accompanied by the perils of over utilization prompted by defensive medicine with interests of the physician potentially overshadowing those of the patient.

Although the contribution of these advances has benefited countless patients, many of the rewards of the practice of medicine have been diminished. In looking back at my 50 years of practicing medicine, recalling my final grand rounds at Charity Hospital, I appreciate the diagnostic skills acquired through history and physical examination, as well as the relationship I had with my patients during my clinical years. To me, this represents the real definition of being a physician. In many cases, these simple tools were often as effective, and certainly more satisfying, than today’s tendency to view the patient as the result of an imaging test rather than a person.

Christopher R. B. Merritt, MD, is a Past President (1986–1988) of the American Institute of Ultrasound in Medicine (AIUM) where he led the development of the AIUM/NEMA/FDA Output Display Standard, and served as a founder of the Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL).

References

  1. Merritt CB, Mann DL, Rogentine GN Jr. Cytotoxic antibody for epithelial cells in human graft versus host disease. Nature 1971; 232:638.
  2. Merritt CRB. Ultrasound demonstration of portal vein thrombosis. Radiology 1979; 133:425–427.
  3. Merritt CRB, Coulon R, Connolly E. Intraoperative neurosurgical ultrasound: transdural and tranfontanelle applications. Radiology 1983; 148:513–517.
  4. Merritt CRB, Goldsmith JP, Sharp MJ. Sonographic detection of portal venous gas in infants with necrotizing enterocolitis. AJR 1984; 143:1059–1062.
  5. Merritt CRB. Doppler colour flow imaging. Nature 1987; Aug 20; 328:743–744.
  6. Merritt CRB. Doppler color flow imaging. J Clin Ultrasound 1987; 15:591–597.
  7. Mendelson EB, Berg WA, Merritt CRB. Towards a standardized breast ultrasound lexicon, BI-RADS: ultrasound. Semin Roentgenol 2001; 36:217–225.
  8. Taylor KWJ, Merritt C, Piccoli C, et al. Ultrasound as a complement to mammography and breast examination to characterize breast masses. Ultrasound Med Biol 2002; 28:19–26.
  9. Berg WA, Blume JD, Cormack JB, et al. Combined screening with ultrasound and mammography vs mammography alone in women at elevated risk of breast cancer. JAMA 2008; 299(18):2151–2163.

Ultrasound in Annual Medicare Wellness Visits?

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Medicare Part B covers many preventive services, such as screenings, shots or vaccines, and yearly Wellness visits, in which a patient’s heart rate, blood pressure, and temperature are evaluated. But, would it be beneficial to add an ultrasound examination?

A team that performs these Wellness visits in a clinic sought to determine whether adding a screening ultrasound examination to the visits would be beneficial for the patients. Six primary care providers, all with advanced ultrasound training, and one ultrasound examiner began a study to find out.

After screening potential patients for the study, each eligible patient gave their consent to be in the study. Note, because their pool of eligible Medicare patients had the following characteristics, they did not represent the nation-wide average:

  • Were at least 65 years old, but not over 85 years;
  • Tended to live independently in an affluent area;
  • Had relatively healthy lifestyles;
  • Had prior access to healthcare;
  • Did not have a documented CT scan of the abdomen or formal echocardiogram in the previous 2 years; and
  • Did not have greater than stage 1 obesity.

Each of the 108 participants underwent an ultrasound examination of the carotid arteries, the heart, and the abdomen, targeting important abnormalities of elderly patients. The patients were not charged for the ultrasound examination.

After the examination, the ultrasound examiner and the primary care provider reviewed the results, discussed them with the patient, and coordinated any needed follow-up care, including 30 follow-up diagnostic items. The patient then completed a 5-question survey about their experience with the ultrasound examination.

Six months later, after the patient’s next Wellness visit, the primary care provider reviewed the patient’s medical record for any follow-up based on the results of the ultrasound examination and assigned each of the 283 abnormalities detected via ultrasound a “benefit score” ranging from –4 (no short-term or potential long-term benefit but serious negative impact occurred because of subsequent care) to 4 (critical clinical benefit, worth all subsequent care). The primary care provider determined the score based on the Medicare reimbursement value of all care received as a result of the ultrasound examination.

Combining the survey results and the abnormality scores, the primary care provider then determined each patient’s net benefit score.

Of all of the abnormalities found, the majority would not have been detected by a traditional physical examination. And although none of them were considered life-threatening, they were frequently markers of chronic conditions, so the primary care provider considered their discovery to be mild to moderately positive.

In conclusion, the study found abnormalities in 94% of the participants. However, only about half of all of the Wellness patients (not just those who participated in the study) would meet the criteria for a screening ultrasound examination, so the examination could not be added to all Wellness visits. For those who qualified, however, in a setting with primary care providers who are experts in ultrasound, the benefit of the examination was rarely negative and often mild to moderately positive, including identifying some new chronic conditions.

To read more about this study, download the Journal of Ultrasound in Medicine article, “An Ultrasound Screening Exam During Medicare Wellness Visits May Be Beneficial” by Terry K. Rosborough, MD, et al. Members of the American Institute of Ultrasound in Medicine can access it for free. Join today!

Interested in learning more about ultrasound? Check out the following posts from the Scan:

Point-of-Care Ultrasound for Internal Medicine: Don’t Forget the Basics

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As specialists in General Internal Medicine, we are excited to see the benefits of incorporating point-of-care ultrasound (POCUS) when assessing medical patients with complex, multi-system disorders. For example, in a patient with heart failure with reduced ejection fraction and chronic obstructive pulmonary disease (COPD) who presents with dyspnea and is found to have diffuse wheezing on auscultation, a number of possible diagnoses exist. Using basic POCUS techniques, findings of asymmetric B-lines, focal pleural irregularity, cardiac findings that seem unchanged from baseline, and a small, collapsible inferior vena cava, increase our suspicion that an infectious precipitant exacerbating the patient’s COPD is the presumptive diagnosis, rather than a primary cardiac cause.

When applied appropriately, POCUS provides real-time data previously not readily available at the bedside. This data can narrow the differential diagnosis [1] and guide intervention. Such benefits of using POCUS to assess medical patients are increasingly known [2–4].  Although new and advanced applications often predominate in the spotlight, basic applications can add a significant amount of information to assist in the care of our patients [5]. The important role that POCUS can play in evaluating medical patients has recently been recognized by the American College of Physicians and Society of Hospital Medicine [6, 7].

As medical educators, we are equally excited about how POCUS can revolutionize bedside teaching—we have seen this tool provide learners with the opportunity to inspect and then confirm the exact location and height of the jugular vein, see then feel a pulsatile liver secondary to severe tricuspid regurgitation, and percuss then visualize a sonographic Castell’s sign [8]. These “aha” moments when our learners see these maneuvers brought to life are incredibly rewarding. However, the excitement that POCUS brings sometimes needs to be balanced by caution.

Despite POCUS being relatively easy to learn, there are multiple pitfalls. The need to apply minimal criteria when acquiring and interpreting images cannot be understated. Just as important as (if not more important than) correctly identifying a positive finding is the ability to recognize when a scan does not meet minimal criteria. Communicating and teaching these limitations to new POCUS users is of paramount importance. Beyond image acquisition and interpretation, achieving competence in clinical integration requires time, repetitive practice, and feedback. As POCUS educators, we frequently see learners flock to advanced applications, such as advanced hemodynamics and detailed cardiac valvular assessments, without necessarily first mastering the basics. Our experience has been that the yield for many of these advanced applications is not high, but the cognitive load in learning them—especially before mastering the basics—is. 

Our approach to using and teaching POCUS is to ensure that we ourselves maintain an appropriate amount of curiosity and humility. We continue to spend time tweaking image acquisition techniques and increasing our understanding of the appropriate uses and limitations of POCUS. This includes expanding our knowledge of the many reasons for false positives and negatives, ensuring our ability to recognize technically limited studies, and maintaining a commitment to finding, applying, and developing the evidence-base to support the use of POCUS for internal medicine. Balancing the tension between experimenting with advanced applications and mastering basic POCUS is sometimes challenging. The steep learning curve of basic POCUS can fool many into thinking mastery has been achieved when there are additional pitfalls to learn.

While we do not wish to dampen learner enthusiasm for high-level applications, we believe there are ways to build learner enthusiasm around basic POCUS. First, we ensure that learners are challenged with cases where clinical integration is complex and nuanced. Emphasis on patient safety and outcomes can help emphasize the need to master basic applications. Second, as educators, we should model a commitment to lifelong learning. Regularly identifying then closing learning gaps can help avoid the illusion that POCUS mastery has been achieved, when in actuality, even basic POCUS applications need to be continually refined and thoughtfully integrated in each unique clinical scenario. This, in addition to encouraging higher-level learners to take a deep dive into high-level applications to appreciate the challenges of these advanced scans, can help maintain while also balancing the excitement of integrating POCUS into the care of complex medical patients. 

REFERENCES

  1. Buhumaid RE, et al. Integrating point-of-care ultrasound in the ED evaluation of patients presenting with chest pain and shortness of breath. Am J Emerg Med 2019; 37(2):298–303.
  2. Filopei J, et al. Impact of pocket ultrasound use by internal medicine housestaff in the diagnosis of dyspnea. J Hosp Med 2014; 9(9):594–597.
  3. Razi R, et al. Bedside hand-carried ultrasound by internal medicine residents versus traditional clinical assessment for the identification of systolic dysfunction in patients admitted with decompensated heart failure. J Am Soc Echocardiogr 2011; 24(12): 1319–1324.
  4. Mozzini C, et al. Lung ultrasound in internal medicine efficiently drives the management of patients with heart failure and speeds up the discharge time. Intern Emerg Med 2018; 13(1):27–33.
  5. Zanobetti M, et al. Point-of-care ultrasonography for evaluation of acute dyspnea in the ED. Chest 2017; 151(6): 1295–1301.
  6. Soni NJ, et al. Point-of-Care ultrasound for hospitalists: A position statement of the Society of Hospital Medicine. J Hosp Med 2019; 14: E1–E6.
  7. Qaseem A, et al. Appropriate use of point-of-care ultrasonography in patients with acute dyspnea in emergency department or inpatient settings: A clinical guideline from the American College of Physicians [published online ahead of print April 27, 2021]. Ann Intern Med. doi: 10.7326/M20-7844.
  8. Cessford T, et al. Comparing physical examination with sonographic versions of the same examination techniques for splenomegaly. J Ultrasound Med 2018; 37(7): 1621–1629.

Janeve Desy, MD, MEHP, RDMS, and Michael H. Walsh, MD, work in the Department of Medicine at the University of Calgary; Irene W. Y. Ma, MD, PhD, RDMS, RDCS, works in the Department of Medicine and Department of Community Health Sciences at the University of Calgary.

Want to learn more about POCUS for General Internal Medicine? Check out the following resources from the American Institute of Ultrasound in Medicine (AIUM):